A new book suggests that fluctuating and high testosterone levels of some pro athletes may also make them more risk-tolerant when it comes to gambling and match-fixing

There are clearly a number of different factors that go into whether a player or team might be susceptible to match-fixing. Certainly, players in competitions where there is less attention and less money on the line have less to lose by fixing a game or two. And in jurisdictions where regulation is lax, it’s less likely that situational fixing – or even the manipulation of an entire game – will be noticed by officials.

Low Leagues Are Easy Targets

That’s why lower leagues are often the targets of fixers. Since the level of play and the wages are both rather low, it’s both harder to tell when a player or two isn’t trying their best, and also easier to buy off those same players. For instance, the lowest levels of Australian soccer have often been targeted by Asian match fixers, as it’s a likely spot to find places where a fix could occur, and the matches take place at a prime time for Asian gamblers’ betting cycles.

But while these standard elements certainly play a major role in match fixing, emerging evidence is starting to suggest that a more fundamental factor may be behind both athletic prowess and a susceptibility to gambling and fixing contests. In fact, at some level, it might just be genetic.

The theory is still in development, and even those who advocate for it say that the link is tentative and needs more investigation. But there are some interesting links that could show this theory to have at least some merit.

Several academic studies have begun to show a link between success in athletics and a penchant for risk-taking. For instance, a 2010 study showed that among 700 pairs of brothers who played professional baseball, younger brothers were far more likely to take risks. That allowed them to have more success at the plate, and also led to them stealing more bases in their careers.

Risk-Taking: Pros and Cons

If being willing to take some risks is an advantage on the playing field, though, it may be a less desirable trait in other aspects of life. And that’s where the theory comes into play: could a predisposition to taking risks also mean that athletes are more likely to get caught up in gambling?

According to researchers in the UK, professional athletes in recent years have become far more likely to develop serious gambling addictions than those in previous eras. In fact, they say that it’s the most common vice among athletes today. This may not be that surprising: as athletics have become more professional, players have had to largely shy away from abusing drugs and alcohol to stay in shape, while gambling can be done with no physical impact.

“Events on the field cause testosterone fluctuations,” Epstein said, “so you might expect athletes to be like day traders who, when they win at things, become increasingly less risk-averse.”

That sounds familiar to experts in the field of gambling addiction, who say active and retired players will often bet in order to get the same thrill they experienced on the court. Research has also shown a relatively high percentage of athletes with ADHD, which could also be a factor in impulsive behavior.